Explosive



Patented June 18,

UNITED STATES EXPLOSIVE Willi Briin, Bridgeport, Conn, assignor to Itemington Arms Company, Inc., a corporation of Delaware No Drawing. Application June 3, 1938, Serial No. 211,567

16 Claims.

This invention relates to the production of certain new and hitherto unknown chemical compounds, and uses for such compounds. Such compounds are oxygen deficient, and have suflicient aflinity for oxygen to render them useful as fuels in explosive compositions, particularly ammunition primers and primary detonators.

The present application is a continuation-inpart of applicants prior co-pending application, Serial No. 116,350, filed December 17, 1936.

The novel compounds are salts of certain derivatives of phthalic acid; more specifically, salts of 4-nitro phthalic acid, and double salts of 4- nitro phthalic acid and nitric acid.

The invention comprises the discovery of four different simple lead salts of 4-nitro phthalic acid, namely, a normal salt, a mono-basic salt, a di-basic salt, and a tri-basic salt; also diand tri-basic lead double salts of 4-nitro phthalic acid and nitric acid.

In the preparation of the normal salt, the lead nitrate solution, 5 grams of lead nitrate in cc. of water, is preferably added to the solution of the acid, which solution comprises 2.29 grams of 4-nitro phthalic acid in 42 cc. of one-half normal sodium hydroxide and cc. of water, at a temperature of about 90 C. The yield is 4.15 grams of a salt which is white in color, of low gravimetric density, and forms in thin plates with irregular edges. Its lead content is 47%, approaching the theoretical lead content (47.71%) of the normal lead salt of the acid of the formula CeH3NO2(COO) 2PbH2O. This salt has been maintained at a temperature of 100 C. for a period of five days without loss of water of crystallization.

It will be noted that the quantity, of sodium hydroxide used is somewhat in excess of the quantity theoretically required to neutralize the specified quantity of 4-nitro phthalic acid. The specified quantity was determined by titration. It is probable that the excess acidity (as well as the discrepancy between actual and theoretical lead content of some of the salts to be described) is due to impurities (such as unnitrated phthalic acid) in the 4-nitrc' phthalic acid. While this acid can be secured in small amounts from the manufacturers of fine chemicals, it is not made in quantity and does not have an extensive commercial use. Its preparation in a pure form apparently has not been perfected.

The normal salt when ignited burns rather slowly with the evolution of considerable smoke and a substantial increase in volume, being similar in this respect to the mercury sulphocyanate used in certain fireworks.

The mono-basic salt may be prepared as follows:

A solution of 2.29 grams of 4-nitro phthalic acid in cc. of one-half normal sodium hydroxide is added to a solution of 10 grams of lead nitrate in 100 cc. of water at a temperature of about C. There results a precipitate of 6.6 grams of a nearly white but slightly cream colored substance in small heavy cubical crystals. The lead content of this precipitate is 60.8%, approximating the theoretical lead content (63%) of the mono-basic lead salt of the acid having the formula CsHaNOz (CO0) aPb-Pb (OH) 2.

In the preparation of the di-basic salt, a solution wasprepared containing 2.29 grams of 4- nitro phthalic acid and 2.4 grams of sodium hydroxide in 120 cc. of water. 9.9 grams of lead nitrate were dissolved in cc. of water, and both solutions brought to a temperature of about 90 C. The lead nitrate solution was dropped into the sodium hydroxide solution, resulting in a precipitate of 7.7 grams of a coarse crystalline material having a cream color. Its lead content is about 68.25%, approximating the theoretical lead content of a di-basic lead salt of 4-nltro phthalic acid of the formula CsH3NO2(COO) 2Pb-- 2Pb(OH)2. It contains no nitrate radical, and is thus substantially identified as a simple dibasic salt of the above formula.

If in the procedure outlined for the preparation of the di-basic salt the second solution contains 15 grams of lead nitrate, instead of the 9.9 grams theoretically necessary for the formation of a simple di-basic salt, and the nitro phthalicsodium hydroxide solution is dropped into the lead nitrate solution so that an excess of lead nitrate is maintained, there results a precipitate of 10.6 grams of dense, cream colored, coarsely crystalline material. Its physical appearance does not difier substantially from that of the di-basic salt above described but its lead content is only about 64.6%, and its nitrate content as determined by a nitron reagent indicates that it contains slightly less than 24% of lead nitrate. It thus appears to be a di-basic lead nitrlo phthalate-lead nitrate of the formula Cal-BNO: (COO) 2Pb-2Pb (OH) 2--Pb(NOs) 2.

The theoretical lead content of this compound is 67.5%, and its theoretical lead nitrate content is 26.9%. If in its preparation as above described an allowance is made for impurities in the 4- nitro phthalic acid, the yield is improved and the i lead analysis of the product more nearly approaches the theoretical.

A simple tri-basic salt is prepared as follows:

2.29 grams of 4-nitro phthalic acid are dissolved with 3.2 grams of sodium hydroxide in 160 cc. of water; 13.2 grams of lead nitrate are dissolved in 100 cc. of water; and the two solutions brought to a temperature o'f'iiqbout 90 C. The lead nitrate solution is then "dropped into the sodium hydroxide-nitro phthalic acid solution, and there results a precipitate of fiufiy crystals in the form of needles and bars, which when wet are of a yellow color with a greenish cast but upon drying become white. The yield is 9.5 grams (theoretical yield 11.4 grams). It contains Percent Percent Percent Percent Percent Percent Percent Percent Basic simple or double lead salt of i-nitro phthalic acid 7 8 8 11 Calcium silicide Antimony sulphide"- 7 Lead nitrato-hypophosphite Zirconium. 7 5 Lead siullliihocyanate 10 Guany trosamlno-guanyltetrazene 3 2 2 2 Lead styphnate 21 40 40 38 Mercury iulminate--. Lead nitrate so Barium nitra 20 39 Lead peroxide--- 10 5 Glass 20 20 no nitrate. When a flame is applied to the edge The lead salts of 4-nitro phthalic acid and the of a cake of the material it burns slowly through double salts herein disclosed being entirely new the mass with very little flame or smoke and the compounds, the appended claims are to be broademission of few sparks; when such a cake is ly construed. pulverized it burns somewhat more rapidly but What is claimed is: without flame. The method of preparation and 1. A lead salt of 4- nitro phthalic acid. the yield indicate that it is a simple tri-basic 2. A normal lead salt of 4-nitro phthalic acid. lead salt of 4-nitro phthalic acid of the formula 3, A -ba i 1 d lt of 4-nitro phthalic CeH3NO2(COO)2Pb3Pb(OH)2. acid ggfi g f g g g5 gf gg gf gg 4. A di-basic lead'salt of 4-nitro phthalic acid.

I .l. nitrate is used and the nitro phthalic acid-sodium nu-basic lead salt of r z phzhanc hydroxide solution is dropped into the lead nitrate A lead double Salt of ph ham: acld solution there results a precipitate of 13.8 grams and nit! acid- (theoretical 14.7 grams) of small heavy cubical Ad flae s pos tm p sine as an crystals which are cream colored both when wet ingredient a lead Salt of 911131191110 acidand when dry and containa substantial amount A d fl explosive Composition of the nitrate radical. When a mass of this prep g as an in ed ent a bas c lead salt of 4- cipitate is ignited it burns quite rapidly with the nitro nhtnalic acid emission of a shower of sparks. The ingredients 9. An ammunition priming composition comused in its preparation, the yield and the nitrate prising as an ingredient a basic lead salt of 4- content, indicate that it is a tri-basic lead double nitro phthalic acid. salt of 4-nitro phthalic acid and nitric acid of the 10. An ammunition priming composition comformula prising in approximately the specified proportions CeI-I NO (COo) Pb 3Pb(QI-I) FPMNQQQ the following ingredients:

If the same procedure is followed using 15 Per cent grams of lead nitrate a precipitate is secured Guanylmtmsaminoguanyltetmzene 2 which contains 70.4% of lead and 10.55% of lead Lead styphnate nitrate; it is obviously amixture of the simple tribasic lead salt of Phthanc acldu 8 basic salt and the double tri-basic salt. Lead nitrate 30 The described simple and double salts, .particu- Glass larly the eand ii-basic Simple and the 11 A deflagrating explosive composition comg; 3232:1 2??? gg g g ggf gg prising as an ingredient 'a double salt consisty elding material burn quite rapidly, and by 1: 5; basic lead 4-mtm phthafmte and lead-mreason of this property they are useful as fuel ingredients of deflagrating explosive composi- 12. A deflagrating explosive composition comprising as an ingredient a double salt consisting of di-basic lead 4-nitro phthalate and lead nitrate.

13. A deflagrating explosive composition comprising as an ingredient a double salt consisting of tri-basic lead 4-nitro phthalate and lead ni-- trate.

14. An ammunition priming composition com-f prising in approximately the specified proportions the following ingredients:

Glass 20 15. A double salt consisting of di-basic lead 4-nitro phthalate and lead nitrate.

16. A double salt consisting of tri-basic lead 4-nitro phthalate and lead nitrate.

WILLI BRt'iN. 

